Authors: D. F. Swaab
There was an enormous fuss when some male-to-female transsexuals took part in competitions as womenâas if one would undergo the protracted misery of a sex change just to win a medal. However, Renée Richards, an MtF transsexual, won a court case in the United States that allowed her to compete in women's tennis. Since 2004, following research by Louis Gooren, a Dutch professor of transsexology, MtF transsexuals have been allowed to take part in sports two years after gender-reassignment surgery if their hormone levels have “normal” values and their sex change has been formalized. The Canadian transsexual cyclist Kristen Worle sought to participate officially in the Beijing Olympics but, alas, failed to qualify.
In 1999 it was decided to abolish the collective sex tests for the Olympic Games. A team of specialists would instead be on constant standby to investigate any problems professionally. This was a distinct improvement on applying a simple but fallible test to a very complex problem. As of May 1, 2011, the International Association of Athletics Federations (IAAF) has opted for the most logical and simple approach. Investigations are now confined to the level of testosterone in the blood. If women's testosterone levels are lower than would be normal in men, they may participate in women's events. An exception is made for individuals with androgen insensitivity syndrome like Maria Patino. At long last a logical solution has been found that doesn't entail someone suddenly being told that they are not a woman but a man. And it's a good solution, because it's all about the effect of testosterone on our muscles. But it will be interesting
to see how the IAAF deals with the boundaries of normal values.
How did people ever get the idea that exerciseâapart from the mental kindâis healthy?
Over the last hundred years, the average life expectancy has risen from forty-five to nearly eighty years, even though we have simultaneously become much less physically active. You might happily conclude from this that it pays to be lazy. But strangely enough, no one does. There are few things people agree on in this world, but it is a truth universally acknowledged that we don't get enough exercise these days. As a result, you can no longer enjoy a pleasant stroll through the woods without being overtaken by panting and sweating joggers, most of whom look as though they're in agony. Any self-respecting company sponsors athletes; marathons are organized for children with cancer. Amsterdam's Academic Medical Center, which should know better, organizes an annual charity run. At 6:45
A.M.
an exercise initiative aimed at Dutch senior citizens bombards the nation with images of elderly people leaping about in leotards.
Where on earth did people get the idea that sports are good for you? Certainly not by working in an emergency room on Sunday mornings, as I used to do. Early January 2009 was a case in point. The Dutch canals froze, whereupon half the people of Holland dug out their skates and hit the iceâin many cases literally. Hospitals were struggling to cope with the ten thousand extra patients being admitted with broken bones, hypothermia, and the like. Hardly a contribution to public health, any more than the special flights made every year to transport Dutch skiers with broken legs back from winter sports regions. There are 1.5 million sports injuries a year in the Netherlands, half of which require medical treatment. If sports were
banned, all our waiting lists would disappear overnight. We already know that boxers can end up with lasting brain damage (see earlier in this chapter). The risk run by kickboxers turns out to be ten times as great. Soccer players lose brain cells, too, what with all that heading and the odd elbow in the face. Long-distance runners have been dropping dead since the very first marathon in Greece. Some 15 percent of paraplegics incurred their injuries from sports. The American actor Christopher Reeve, famous for playing the role of Superman, was paralyzed for life after breaking his neck in a fall from his horse.
A compulsion to exercise can also be a sign of disease; it is, for instance, a typical symptom of anorexia nervosa (see
chapter 5
). People with anorexia often work out obsessively. Decades ago, long before jogging was fashionable, the neurologist Frans Stam was looking out of his window at Valeriusplein, a square in Amsterdam. To his amazement he saw someone emerge from one of the houses opposite his, run around the square several times at high speed, and then go back in again. This process was sometimes repeated several times a day. A few months later, the man in question was hospitalized; he proved to have Pick's disease, a form of dementia in which the prefrontal cortex atrophies, which often first manifests itself in behavioral disorders. Since Stam told me that story, I've always been a bit wary of joggers. No one seems to worry very much about the increased risk that athletes have of contracting ALS, a form of motor neuron disease, or about the fact that up to 150 people a year in the Netherlands suddenly drop dead on playing fields or in gyms. Bodybuilders happily inject themselves with anabolic steroids and in the past took growth hormone preparations made from human pituitaries that sometimes turned out to be infected with Creutzfeldt-Jakob disease, a type of dementia that progresses very rapidly. It does indeed seem, as the Dutch magazine
Vrij Nederland
once jokingly claimed, that half the population takes part in sports, while the other half drives them to the hospital.
You might argue that these are just some of the minor risks of a
lifestyle that on the whole makes people long-lived and healthy. But you'd be on shaky ground. The studies and statistics that allegedly support the benefits of exercise aren't based on properly controlled trials but on comparisons of groups of people who themselves opted to take up a sport (or not). This self-selection makes it impossible to draw any valid conclusions. Conversely, as far back as 1924, Raymond Pearl found that extreme physical exertion actually shortened lifespan. This appears to apply to the whole animal kingdom. Comparative research by Michel Hofman at the Brain Institute shows that two factors determine our lifespan: metabolism and brain size. The higher the metabolism, the shorter the lifespan. This ties in with the finding that top athletes at Harvard have shorter lifespans than their non-athletic classmates. So the enormous physical effort involved in exercise might even have a life-shortening effect. The American researcher Rajinder Sohal found that the more flight movements a fly makes, the sooner it dies. If you prevent flies from wasting energy by confining them within two plastic plates, so that they can't fly, they live up to three times longer. A single organ, the brain, also affects length of life: The larger and more active it is, the longer your lifespan. Conversely, brains that are too small, for instance because of microcephaly or Down syndrome, shorten lifespan. Stimulating the brain also appears to delay the onset of Alzheimer's and can mitigate the symptoms of this disease (see
chapter 18
). Eminent scientists are said to have larger brains and to live longer. You can increase brain size by providing stimuli in the form of new and constantly varying information, for instance by giving children an enriched environment (see
chapter 1
). So it would appear to be healthier to watch sports than to take part in them. And if you're really bent on taking up a sport, how about chess?
The functions of the prefrontal cortex came to light as a result of brain damage and disorders.
As with many human brain structures, the functions of the prefrontal cortex (
fig. 15
) came to light only as a result of accidents, operations, and neural disorders. In 1848, a railroad construction foreman named Phineas Gage was stuffing blasting powder, fuse, and sand into holes with an iron rod when an explosion blew the thirteen-pound rod right through his head, causing half a teacupful of his brain to be spilt on the ground. Amazingly, Gage not only survived the accident, he remained fully conscious in the aftermath of his terrible injury. But he underwent a marked personality change. Previously hardworking and responsible, he became fitful, capricious, aggressive, and foulmouthed, and he ended up losing his job. As his friends put it, “Gage was no longer Gage.” Indeed, one of the functions of the prefrontal cortex, which had been damaged in Gage's accident, is to ensure that we conform to social norms.
Another one of its functions was discovered shortly afterward, when Paul Broca, a physician working at a hospital in Paris, carried
out an autopsy of a patient who had been nicknamed “Tan,” because “tan” was the only distinguishable sound he could make. His inability to speak proved to be caused by an infarction in the frontal lobe of his left cerebral hemisphere (
fig. 8
). This region of the brain, which is responsible, among other things, for the production of grammatically correct sentences, is now known as Broca's area. Damage to this region after a stroke leaves patients with aphasia, that is, speech disorders.
A hundred years after Gage's accident, during the “heyday” of psychosurgery, lobotomies were performed to destroy the prefrontal cortex deliberately. Misinterpreted findings in animal studies suggested that lobotomies could help schizophrenia sufferers or violently aggressive individuals. The film
One Flew over the Cuckoo's Nest
memorably shows how the operation transforms a rebellious and difficult patient into an apathetic zombie who just sits in a chair, gazing vacantly into space. Of course, he is now much more manageable from a clinician's point of viewâand that was deemed important when considering a lobotomy. Eventually, doubts were increasingly voiced about whether lobotomies were an effective treatment for aggressive behavior. It may be that the medical world was alarmed by the fate of the Nobel Prizeâwinning surgeon who devised the procedure, António Egas Moniz, who was shotâby a disaffected patient, it was claimedâand spent his remaining years in a wheelchair.
In 1951, 18,608 lobotomies were performed in the United States, mainly on schizophrenia patients. The vogue was started by Walter Jackson Freeman, nicknamed “Jack the Brainslasher,” who enthusiastically performed the operation all over the United States, touring the country in a van that he called his “lobotomobile.” After stunning a patient with an electric shock, he would hammer an ice pick through the back of the eye socket into the frontal lobe, thus destroying the connection with the other parts of the brain. The effect of the procedure wasn't at all understood at the time. Pope Pius XII announced that the Church did not oppose lobotomy “as long as free will is retained, even if there be some loss of personality”; another
high-ranking Catholic added, “If the soul survives death, it can presumably survive a lobotomy.” The operation was later rightly characterized as “partial euthanasia,” because the patients' personalities were blunted, and they became completely apathetic. Doctors eventually stopped resorting to the operationânot from ethical considerations, but because it was rendered unnecessary by the emergence, in the mid-1950s, of psychoactive drugs. The damage caused to so many individuals by lobotomies was never properly documented, though it became abundantly clear from the operations that the prefrontal cortex played a crucial role in expressing personality and taking initiative.
In his book
The River That Flows Uphill
, William H. Calvin tells the following anecdote:
The famous Montreal neurosurgeon Wilder Penfield had a sister â¦Â who was one of those cooks who could spend four hours preparing a five-course meal and have everything turn out just right. Nothing got cold or overcooked, because it was always ready to come off the burner or out of the oven just when it was needed. Now that's truly a precision-timing scenario. But Penfield's sister began to lose this ability. Over the course of several years, the holiday family dinners began to distress her because she couldn't get properly organized as she had used to. For ordinary dinners she was still a good cook. Most physicians wouldn't have picked up on such subtle clues. But Penfield's clinical instincts told him that she might have a frontal lobe tumour. She did. He operated. She recovered.
The removal of much of the right prefrontal cortex along with the tumor, however, did nothing to restore her ability to organize. Fifteen months after the operation she prepared a dinner for five, which failed disastrously due to her inability to take initiative and make choices, typical functions of the prefrontal cortex.
The prefrontal cortex also ensures that we conform to social
norms. In Pick's disease, a rare neurodegenerative disease, and other forms of frontotemporal dementia, the prefrontal cortex becomes severely damaged. These conditions cause the prefrontal cortex tissues to shrink until they resemble a walnut in its shell (
fig. 30
). The early stages of Pick's disease aren't so much marked by memory failure as by behavioral disorders, general dementia only setting in many years later. A professor who developed Pick's disease suffered from a loss of decorum in its early stages, famously urinating against a salon piano. Interestingly, microscopic postmortem analysis at the Netherlands Brain Bank of the brains of patients who had been diagnosed with Pick's disease revealed an absence of “Pick bodies” in the vast majority of cases. Pick bodies are the disease's defining feature, taking the form of protein tangles that appear as large bodies in neurons. In the last decade it was discovered that some of the patients thought to have Pick's disease actually had chromosome 17 frontotemporal dementia caused by tau gene mutations. During the early stages of the disease, they also exhibited behavioral deviations, such as disturbed social behavior, hyper- or hyposexuality, alcoholism, aggressive behavior, depression, and schizophrenic tendencies. New forms of dementia are still being identified.